Machines such as, for example, track-type tractors, dozers, motor graders, wheel loaders, and the like, are used to perform a variety of tasks. For example, these machines may be used to move material and/or alter work surfaces at a worksite. The machines may be manned machines, but may also be autonomous or semi-autonomous vehicles that perform these tasks in response to commands remotely or locally generated as part of a work plan for the machines. The machines may receive instructions in accordance with the work plan to perform operations, including digging, loosening, carrying, and any other manipulation of materials at the worksite.
It may be desirable to ensure that the machines perform these operations such that the materials are moved in an efficient manner. More particularly, in repetitive operations, it may be especially desirable to ensure that the locations at which the machines begin to alter the work surface, or the profiles along which the machines alter the work surface, are selected in a way that maximizes efficiency and productivity. Some conventional systems, such as disclosed in U.S. Pat. Appl. Publ. No. 2014/0012404, published on Jan. 9, 2014 and entitled “Methods and Systems for Machine Cut Planning,” plan cut locations based on predetermined cut volume estimations. While such techniques may greatly assist in the planning processes and the overall excavation, there is still room for improvement.
A standard cut profile in autonomous dozing is generally composed of three regions, including a blade-in-air region, a blade-load region, and a blade-carry region. In the blade-in-air region, a dozer is typically reversing after a cut and positioning a blade implement to make contact with the work surface. Once contact is made with the work surface and a cut is initiated, the blade is loaded with material in the blade-load region and generally moved downward to a target carry surface. In the blade-carry region, the blade carries the loaded material to a crest of the worksite. As this process is repeated, the work surface elevation gradually changes and the profile of the blade-load region is updated accordingly. However, autonomous carry passes often adjust the blade height while in the blade-carry region which can result in unwanted deviations from the planned profile.
Theoretically, conventional cut and carry passes, along with occasional ripping passes, may be repeated to execute clean passes according to the planned profile and avoid unwanted deviations. In actual practice, however, cut and carry passes may deviate from the planned profile due to factors such as hard soil, insufficient ripping, degradations in position estimation, hump building, large rocks, boulders or other embedded obstacles, and the like. Limitations in the actual process of planning for conventional cut and carry passes are also factors. For instance, conventional processes are limited to profiles formed using S-shaped Gaussian curves, which cannot sufficiently adapt to negative volumes or valleys in the terrain that dip below the target profile, bumps in the terrain that extend above the pass target, or the like.
Accordingly, there is a need for grade control or cleanup passes that can reduce inconsistencies in the terrain, minimize operator involvement, and help improve productivity of the overall excavation. Furthermore, there is a need for cleanup pass profiling systems and methods that provide more versatile means for correcting surface irregularities, such as by shaving, snaking or otherwise cutting bumps and/or small valleys. The present disclosure is directed at addressing one or more of the inefficiencies and disadvantages set forth above. However, it should be appreciated that the solution of any particular problem is not a limitation on the scope of this disclosure or of the attached claims except to the extent express noted.